Seating Bullet

BCRiverBoater

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Jan 18, 2008
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Location
Fort St. John, BC
I am looking for the easiest way to accurately seat a bullet. I have read a lot on this subject. How do you accurately know how close to your lands you are? I have tried several tricks to test rifle for seating depth and I know I can do better. I am going more by factory loads, feel and research. I need the easiest technical way to get best seating depth for your rifle.
 
Different barrels like bullets set at different jumps to the lands so if you know what 1 barrel is doing it will not nessarly hold true for another. I have plaied with my .22-6mm a fair amount and found that different load and powders shoot best with different jumps, and some jammed into the lands, with the same bullet. To know exactly How far your jumping is not critical, it is only nessary that you know what AOL shoot best with what load.
 
The ONLY way to learn the best seating depth for your rifle is to experiment with it. There are no secret ways to do anything.

Right. Years ago some benchrest shooters who set up a 100 yrd range inside a warehouse (in St. Louis, as I recall) found best accuracy with lands just engraving the bullet. Anyway, that's a starting point.

Polish dummy round bullet with 4-0 steel wool between various depth settings, and record length of engraved mark.

Five rounds each at various settings (on an off lands) should indicate a "sweet spot" for that particular load/rifle.

Caveat: don't set out so far that (1) the bullet sticks in lands and is pulled from the case when cartridge is extracted (this yields receiver full of powder and much cursing). (2) make sure your reloaded cartridge is not too long for the magazine box.
 
I do all my bullet seating depth with the comparator. The Stoney point comparator is now the Hornady Comparator. You still need to figure out where the ogive of the bullet your loading touches the lands in that rifle though. I did the cleaning rod method and that worked good but I also did it the way the Lyman's 48th edition suggested to do it to measure where your ogive makes contact with the lands and I personally feel is an accurate way. Take a unsized case (aka fired formed) that the bullet your loading will slide into easily and without the bullet in it make a very slight indention on the case neck by just slightly putting pressure on the side of the case neck against your bench, this will flatten the case neck just enough to make the bullet stay in the case but not very tight. Put the bullet just barely into the case just enough to hold it. Then blacken the bullet with a felt marker and gently put it into the chamber of your rifle and carefully close the bolt and lock it. This will push the bullet back into the case as it touches the lands. Take it out being careful not to disturb the bullet and carefully pull the bullet back out of the case so you can see where the black has been scraped off or the line made by the bullet being pushed back into the case. Push the bullet back into the case exactly to where you can see the line in the black and the case mouth line up. Now measure the OAL of your bullet (I use a comparator and measure the ogive). They recommend you do this procedure 3-5 times measuring everytime to make sure you get a consistant measurement and that will be the precise measurement of the distance between your bolt face and the lands of your rifle. You will need to do this for each different bullet you load. I found too that depending on bullet model and guns you can't always seat just off the lands. I am reloading a Rem 700 bdl 300 saum with 165 gr Scirocco II and can only seat them a little bit farther out than factory to still be able to get them to cycle through my magazine. If I seat them just off the lands they won't even come close to fitting in the magazine. Could use it as a single shot I guess.
 
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Keep the same "reference" bullet in a small tube marked for use later. Sinclair int sells the tubes cheap. As bullet ogives vary, it is important to use the same bullet to measure each time to monitor any change.

BH
 
The easiest method I have found,is to make a long dummy round,no primer or powder,just in case the bullet jams in the rifling,no powder to clean up if it does.You will need to do this with each different style of bullet you intend to use.
Soot the bullet with a candle,and chamber the round,the bullet should be pushed back into the case,with about .020"-.050" of the shank into the lands.Repeat this,by seating the bullet in your dies,until a sooted bullet comes out with no rifling marks.Measure OAL at this point,make a note of it,and then with another fresh bullet/case,wind out your seating stem one full turn,seat the new bullet/case at this measurement (RCBS/Redding) this will be equivalent to .036".This should be in the vacinity of .030" off the lands.Do not soot this bullet yet,chamber,make sure there are no rifling marks,and continue.Seat deeper,by 1/8 turn at a time while chambering each time,as soon as you touch the rifling again,back out 1/8 turn and measure,make a note,this should be about .005"-.006" off the lands.By comparing the two you can get your OAL just right.
Soot that bullet,and see if there are rifling marks ALL around the shank,if they are only on one side that means the ejector is tipping the bullet to one side.By adjusting your seating stem with small turns,1/8 is fine,you should be able to get the bullets just touching,say .005",or just missing.
KEEP this dummy round as a reference,and you can adjust the seating stem to whatever distance you want into the lands or out of the lands.
If this fails,you'll have to get an ogive comparator from Sinclair etc.
MagnumManiac
gun)
 
Seeing as I've been reloading for close to 45 years, and did not have the advantage of having all the tools I could have used in my beginning stages, I did it the old fashioned way.

I would dummy load a bullet long, light up a candle & smoke the bullet black. Then load, and reload into the chamber utill the lands stopped engraving their marks into the bullet.

At that point, I would play with the adjustments in & out in very tiny adjustments, until I found the most accurate load.

Yes, trying different bullets took a lot of fiddling around, but eventually one found a very accurate load.

Richard
 
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